Tiamat JP has a lot of Oceanic players :)

Switched from Behemoth NA during EA as I was getting such bad lag & always got hit by AOE's when well out of range ~.~ tis so much better now ^^

To my understanding these are the 'official' Oceania servers:
JP Legacy - Masamune
JP New - Tonberry
JP New - Tiamat
NA Legacy - Sargatanas
NA New - Behemoth

Not sure which ones are still open to new characters though~